BOT (build-operate-transfer) project delivery systems have provided effective routes to mobilize private sector funds, innovative technologies, management skills, and operational efficiencies for public infrastructure development. However, many countries and regions lack BOT expertise and experience. Hong Kong, one of the pioneers in optimizing private sector participation in infrastructure development, has developed five large tunnels on the BOT basis since the late 1960s, the first of which recently completed its franchise period and entered into the posttransfer operation phase. Experience and lessons gained in formulating and managing BOT projects over more than 30 years have enabled the Hong Kong government to develop a well-structured BOT framework. This proven BOT model is useful for countries and regions lacking such expertise and still in need of BOT-based infrastructure. This paper discusses key development aspects of the five BOT tunnels, including feasibility study; tender selection; legal, financial, and land issues; design and construction; operation and maintenance; transfer; and posttransfer management.